Health Library

How Does Your Garden Grow?

For many of us, spring means gardening--and our pursuit of greener grass or pest-free flowers may lead us to fertilizers, pesticides and herbicides.

Recent studies, however, raise a red flag on chemical use, pointing to a possible link between herbicides and pesticides and diseases such as non-Hodgkin's lymphoma, other lymphoproliferative cancers, Parkinson's disease and other neurological problems such as memory loss. Experts are calling for more research, but the home gardener should play it safe.

Chemicals designed to kill or control pests and weeds can be highly toxic. Carefully read the directions on all the labels. Used incorrectly, pesticides can and do poison people and pets, kill beneficial bugs and taint soil and groundwater, experts say. So before you uncork your chemicals, experts suggest you ask several questions:

What is your garden problem?

Is it caused by a weed, an insect or a disease?

Is the problem serious enough to require an herbicide or pesticide?

If chemicals are needed, what's the safest one--and when should you use it?

Fertilizers

In general, homeowners tend to use too much fertilizer, say experts at the EPA. The agency recommends a soil test before adding any nutrients.

For about $10, you can learn whether your lawn needs fertilizer--and what kind. Soil kits are available at gardening centers and county extension offices.

Too much fertilizer can make grass grow too quickly and develop weak roots. Overfertilizing flowering plants will encourage them to grow more leaves--and cut back on flowers.

Lawn fertilizers are often sold in combination with herbicides. When applied improperly, the herbicides make their way to garden plants and trees causing poor or abnormal growth. If your lawn is not infested with weeds, avoid combination products if possible.

Pesticides, herbicides

If you decide to use a pesticide or an herbicide, the EPA says you should zero in on the problem: What kind of weed is it? What kind of insect? What kind of plant is the insect attacking?

Timing is also critical. Too early or too late in the season may not be effective. Some chemicals require that you water after applying them, while others need dry conditions.

The experts stress safety precautions when using any chemicals.

Consider planting pest- and disease-resistant plants whenever possible. The variety of attractive resistant plants is increasing each year and there is a large selection to choose from. This cuts the need for use of pesticides and fungicides.

Alternatives to chemicals

According to the EPA, using nonchemical treatments is usually more effective for longer periods of time. One way to cut back on herbicide use is to mulch, particularly with annual plants. Mulching keeps down weed growth. You can use beneficial predators to eat certain pests. Consider using ladybugs to rid your cherry trees, roses and other plants of aphids. Praying mantises kill many harmful garden insects. These helpful insects can be purchased from most nurseries.

Check with your garden center or extension office for more nonchemical alternatives.

Another approach: vigilance. Pick off that weed or bug as soon as it appears.

Seeds of safety:

Wear rubber gloves, long sleeves, long pants and eye protection. You may need a respirator, hat or shoes. Don't wear leather; it can absorb chemicals.

Use separate spray systems for herbicides and pesticides so residues don't mix.

Mix just enough pesticide for the problem. Dry pesticides can be stored for a season. Discard liquid pesticides through hazardous waste programs.

Store chemicals in original containers to avoid the possibility of poisoning.

Use a 1- to 3-gallon hand-held sprayer, and use water to look for leaks or a plugged nozzle.

Take special care when mixing pesticide. Have an adult nearby in case of accident. Follow label directions precisely. Have water, soap, towels and a hose handy in case of a spill. Mix in a well-ventilated area.

Keep other people and pets away when applying a pesticide. The label will say whether to bar children and pets from treated areas.

Clean the applicator and sprayer thoroughly after use. Rinse it with water and a small amount of detergent, then rinse twice more with water.

When you finish cleaning up, wash your clothes (not with other clothing) in hot water with strong detergent. Take a hot shower; wash your hair.

Reading labels

The EPA, which regulates the use of pesticides and other chemicals, offers this explanation of toxicity warnings:

Danger-Poison. These are the most toxic pesticides and should be handled with extreme care.

Warning. These are moderately toxic and should be handled with care.

Caution. These are slightly toxic materials that are still poisonous. Handle as you would any poison--carefully.